Note: Descriptions are shown in the official language in which they were submitted.
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SECTOR INTERFERENCE MANAGEMENT BASED ON INTER-SECTOR
PERFORMANCE
Claim of Priority under 35 U.S.C. 119
[0001] The present Application for Patent claims priority to Provisional
Application No. 61/028,497 entitled ADAPTIVE ALGORITHMS FOR
INTERFERENCE MANAGEMENT MESSAGING WITH INTER-SECTOR
FAIRNESS IN A WIRELESS NETWORK filed February 13, 2008, and assigned to the
assignee hereof and hereby expressly incorporated by reference herein.
Reference to Co-Pending Applications for Patent
[0002] The present Application for Patent is related to the following co-
pending
U.S. Patent Applications:
"PREAMBLE DESIGN FOR A WIRELESS SIGNAL" by Aamod
Khandekar et at., having Attorney Docket No. 080269, filed concurrently
herewith,
assigned to the assignee hereof, and expressly incorporated by reference
herein;
"PREAMBLE DESIGN FOR A WIRELESS SIGNAL" by Aamod
Khandekar et at., having Attorney Docket No. 080278U1, filed concurrently
herewith,
assigned to the assignee hereof, and expressly incorporated by reference
herein; and
"PREAMBLE DESIGN FOR A WIRELESS SIGNAL" by Aamod
Khandekar et at., having Attorney Docket No. 080278U2, filed concurrently
herewith,
assigned to the assignee hereof, and expressly incorporated by reference
herein; and
"PREAMBLE DESIGN FOR A WIRELESS SIGNAL" by Aamod
Khandekar et at., having Attorney Docket No. 080278U3, filed concurrently
herewith,
assigned to the assignee hereof, and expressly incorporated by reference
herein.
"BACKHAUL SIGNALING FOR INTERFERENCE AVOIDANCE" by
Aamod Khandekar et at., having Attorney Docket No. 080694, filed concurrently
herewith, assigned to the assignee hereof, and expressly incorporated by
reference
herein.
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BACKGROUND
1. Field
[0003] The following relates generally to wireless communication, and more
specifically to providing idle mode mobility management for multiple mobile
communication environments.
II. Background
[0004] Wireless communication systems are widely deployed to provide various
types of communication content such as, e.g., voice content, data content, and
so on.
Typical wireless communication systems can be multiple-access systems capable
of
supporting communication with multiple users by sharing available system
resources
(e.g., bandwidth, transmit power). Examples of such multiple-access systems
can
include code division multiple access (CDMA) systems, time division multiple
access
(TDMA) systems, frequency division multiple access (FDMA) systems, orthogonal
frequency division multiple access (OFDMA) systems, and the like.
[0005] Generally, wireless multiple-access communication systems can
simultaneously support communication for multiple mobile devices. Each mobile
device can communicate with one or more base stations via transmissions on
forward
and reverse links. The forward link (or downlink) refers to the communication
link
from base stations to mobile devices, and the reverse link (or uplink) refers
to the
communication link from mobile devices to base stations. Further,
communications
between mobile devices and base stations can be established via single-input
single-
output (SISO) systems, multiple-input single-output (MISO) systems, multiple-
input
multiple-output (MIMO) systems, and so forth.
[0006] One important aspect of mobile communication technology is managing
interference among transmitters. A typical cell of a cellular phone site, for
instance,
utilizes multiple transceiver base stations to communicate with user terminals
within the
cell. Transmission area of the base stations typically overlap, such that a
single receiver
often obtains several overlapping signals at a given point in time.
Accordingly, signal
interference results at such receivers, potentially reducing signal clarity
and cell
communication quality if left uncorrected.
[0007] Many mechanisms exist for reducing intra-site interference. Some
involve utilizing MISO and MIMO transceivers that can tolerate higher levels
of
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interference, due to improved signal analysis at the receiver. Newer
modulation
techniques, such as orthogonal multi-carrier modulation (e.g., as utilized
with
orthogonal frequency division multiplexing [OFDM]), can effectively reduce
signal
interference. OFDM employs orthogonal sub-carrier frequencies to greatly
reduce
cross-talk interference among carrier signals. Another technique includes
requesting
transmission power reduction of a dominant interferer on one or more channel
resources. If transmission power of the interferer is maintained within an
acceptable
range, overlapping signals on a channel resource can often be tolerated at a
receiver.
[0008] Mobile communication systems are in constant state of flux, however, as
new research and technologies are discovered. Architectural changes in mobile
technology are implemented to increase data rates, bandwidth, or to progress
to all-data
communications. The interference problem typically must be re-visited for each
new
technology, to determine whether the balance provided by previous interference
management mechanisms will be disturbed. Thus, signal interference management
is an
ongoing problem, requiring new solutions as new mobile communications
technologies
are implemented.
SUMMARY
[0009] The following presents a simplified summary of one or more aspects in
order to provide a basic understanding of such aspects. This summary is not an
extensive overview of all contemplated aspects, and is intended to neither
identify key
or critical elements of all aspects nor delineate the scope of any or all
aspects. Its sole
purpose is to present some concepts of one or more aspects in a simplified
form as a
prelude to the more detailed description that is presented later.
[0010] The subject disclosure provides interference management for a mobile
wireless access network (AN) based on performance metrics of sectors of the
AN.
Performance metrics can include various quality of service (QoS) parameters,
such as
average data rate, median data rate, meeting guaranteed bit rate requirements,
and/or the
like. Accumulation of resource utilization messages (RUMs) at a sector can be
based at
least in part on a performance metric of that sector as compared with one or
more
neighboring sectors. In at least one aspect, multiple sector performance
metrics can be
aggregated and RUM accumulation rate of each sector is determined based on the
aggregated metric. Accumulation rate can be managed over time and changed as
sector
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and/or aggregated metrics change. Accordingly, accumulation and utilization of
RUMs
is based on inter-sector fairness to optimize average sector transmission
quality of the
mobile AN.
[0011] In one or more aspects, disclosed is a method of managing mobile
communications. The method can comprise obtaining, at a sector of a mobile AN,
a
performance metric for at least one neighboring sector. Furthermore, the
method can
comprise implementing inter-sector resource utilization fairness based at
least in part on
the performance metric of the neighboring sector(s).
[0012] According to other aspects, provided is an apparatus that manages
wireless communications. The apparatus can comprise a data collector that
obtains, at a
sector of a mobile AN, a performance metric for at least one neighboring
sector. In
addition, the apparatus can comprise a management module that implements inter-
sector
resource utilization fairness based at least in part on the performance metric
of the
neighboring sector(s). Further, the apparatus can comprise memory that stores
one or
more of obtained performance metric data, instructions for process modules of
the
apparatus or results of process operations and a processor that executes
process module
instructions stored in the memory to implement functions of the apparatus.
[0013] In one or more aspects, disclosed is an apparatus configured to manage
mobile communications. The apparatus can comprise means for obtaining, at a
sector of
a mobile AN, a performance metric for at least one neighboring sector.
Additionally,
the apparatus can comprise means for implementing inter-sector resource
utilization
fairness based at least in part on the second performance metric of the
neighboring
sector(s).
[0014] According to other aspects, disclosed is a processor configured to
manage mobile communications. The processor can comprise a first module that
obtains, at a sector of a mobile AN, a performance metric for at least one
neighboring
sector. Further, the processor can comprise a second module that implements
inter-
sector resource utilization fairness based at least in part on the performance
metric of
the neighboring sector(s).
[0015] Further to the above, provided is a computer-readable medium
comprising computer-readable instructions configured to manage mobile
communications. The instructions can be executable by at least one computer to
obtain,
at a sector of a mobile AN, a performance metric for at least one neighboring
sector.
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Further, the instructions can be executable by at least one computer to
implement inter-
sector resource utilization fairness based at least in part on the performance
metric of
the neighboring sector(s).
[0016] According to one or more additional aspects, disclosed is a method of
facilitating wireless communication. The method can comprise obtaining an over-
the-
air (OTA) transmission that comprises a signal performance metric of a mobile
base
station. The method can additionally comprise facilitating inter-sector
resource
utilization fairness at least in part by forwarding the signal performance
metric to a
serving mobile base station.
[0017] According to other aspects, provided is an access terminal (AT). The AT
can comprise a receiver that obtains a first OTA transmission comprising a
signal
performance metric of a mobile base station. The AT can further comprise a
routing
module that facilitating inter-sector resource utilization fairness at least
in part by
wirelessly transmitting the signal performance metric to a serving mobile base
station.
In addition, the AT can comprise memory that stores data and process modules
for the
AT and a processor that executes process module instructions to implement
functions of
the AT.
[0018] In still other aspects, disclosed is an apparatus that facilitates
wireless
communication. The apparatus can comprise means for obtaining a first OTA
transmission comprising a signal performance metric of a mobile base station.
The
apparatus can further comprise means for facilitating inter-sector resource
utilization
fairness at least in part by wirelessly transmitting the signal performance
metric to a
serving mobile base station. Additionally, the apparatus can comprise means
for storing
data and process modules for the apparatus and means for processing that
executes
process module instructions to implement functions of the apparatus.
[0019] In at least one aspect, provided is a processor configured to
facilitate
wireless communication. The processor can comprise a first module that obtains
an
OTA transmission that comprises a signal performance metric of a mobile base
station.
Additionally, the processor can comprise a second module that implements inter-
sector
resource utilization fairness at least in part by forwarding the signal
performance metric
to a serving mobile base station.
[0020] In accordance with one or more other aspects, disclosed is a computer-
readable medium comprising computer-readable instructions configured to
facilitate
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wireless communication. The instructions are executable by at least one
computer to
obtain an OTA transmission that comprises a signal performance metric of a
mobile
base station. Additionally, the instructions are executable by the at least
one computer
to implement inter-sector resource utilization fairness at least in part by
forwarding the
signal performance metric to a serving mobile base station.
[0021] To the accomplishment of the foregoing and related ends, the one or
more aspects comprise the features hereinafter fully described and
particularly pointed
out in the claims. The following description and the annexed drawings set
forth in
detail certain illustrative aspects of the one or more aspects. These aspects
are
indicative, however, of but a few of the various ways in which the principles
of various
aspects can be employed and the described aspects are intended to include all
such
aspects and their equivalents.
BRIEF DESCRIPTION OF THE DRAWINGS
[0022] Fig. 1 illustrates a block diagram of an example system that provides
wireless communication in accordance with aspects set forth herein.
[0023] Fig. 2 depicts a block diagram of an example communication apparatus
for employment with a wireless communication environment.
[0024] Fig. 3 illustrates a block diagram of an example system that determines
sector resource utilization message (RUM) accumulates rates of a mobile AN.
[0025] Fig. 4 illustrates a block diagram of a sample RUM management
apparatus according to aspects of the subject disclosure.
[0026] Fig. 5 depicts a block diagram of RUM management for a mobile AN
according to aspects disclosed herein.
[0027] Fig. 6 illustrates a block diagram of a sample base station that
provides
RUM accumulation management based on sector performance.
[0028] Fig. 7 depicts a block diagram of an example access terminal that
facilitates aggregation of sector performance metrics for sector RUM
management.
[0029] Fig. 8 illustrates a flowchart of an example methodology providing RUM
accumulation based on performance metrics of a mobile AN.
[0030] Fig. 9 depicts a flowchart of a sample methodology for providing RUM
management based on aggregate sector performance metrics.
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[0031] Fig. 10 depicts a flowchart of a sample methodology for facilitating
RUM management based on one or more aspects.
[0032] Fig. 11 illustrates a block diagram of an example system that provides
wireless communication between devices according to aspects of the subject
disclosure.
[0033] Figs. 12 and 13 depict block diagrams of example systems that provide
RUM accumulation based on sector performance metrics of a mobile AN.
DETAILED DESCRIPTION
[0034] Various aspects are now described with reference to the drawings,
wherein like reference numerals are used to refer to like elements throughout.
In the
following description, for purposes of explanation, numerous specific details
are set
forth in order to provide a thorough understanding of one or more aspects. It
can be
evident, however, that such aspect(s) can be practiced without these specific
details. In
other instances, well-known structures and devices are shown in block diagram
form in
order to facilitate describing one or more aspects.
[0035] In addition, various aspects of the disclosure are described below. It
should be apparent that the teaching herein can be embodied in a wide variety
of forms
and that any specific structure and/or function disclosed herein is merely
representative.
Based on the teachings herein one skilled in the art should appreciate that an
aspect
disclosed herein can be implemented independently of any other aspects and
that two or
more of these aspects can be combined in various ways. For example, an
apparatus can
be implemented and/or a method practiced using any number of the aspects set
forth
herein. In addition, an apparatus can be implemented and/or a method practiced
using
other structure and/or functionality in addition to or other than one or more
of the
aspects set forth herein. As an example, many of the methods, devices, systems
and
apparatuses described herein are described in the context of determining a RUM
accumulation rate for one or more sectors of a mobile network based on a
performance
metric of multiple sectors. One skilled in the art should appreciate that
similar
techniques could apply to other communication environments.
[0036] The subject disclosure provides for implementing resource utilization
fairness among sectors of a mobile access network (AN). Fairness can be based,
at least
in part, on a performance metric of one sector of the mobile AN compared with
a
performance metric of another sector. In at least one aspect of the subject
disclosure,
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the resource utilization fairness can be implemented by establishing and/or
adjusting
accumulation of interference avoidance credits (e.g., comprising a resource
utilization
message [RUM]) for sectors of a mobile AN. An interference avoidance credit
can be
utilized to modify interference between neighboring sectors of a wireless AN.
In one
example, an interference avoidance credit can be issued to a neighboring
sector,
requesting that sector modify transmit power on a subset of wireless
resources. The
interference avoidance credit can specify the particular resources for reduced
interference, the degree of modified transmit power, or both. In another
example, the
interference avoidance credit can result in a sector modifying its own
transmit power on
a subset of wireless resources. Because interference typically results from
relative
signal levels obtained at a receiver, modification of a sector's own transmit
power can
also affect interference at terminal devices served by the sector. In addition
to the
foregoing, accruing an interference avoidance credit can lead to no action
taken by a
sector (e.g., no modification or request to modify transmit power). A decision
of what
type of action is most appropriate can be based on performance metric of a
neighboring
sector, performance metric of the sector, an aggregate performance metric of a
plurality
of sectors, interference observed at terminal devices, sector load, or the
like, as
discussed herein.
[0037] One example of an interference avoidance credit is a RUM. RUMs are
messages issued to/by a wireless communication device to instruct nearby
transmitters
to reduce their transmit power. Typically, the decision to issue a RUM is
based on
signal interference at the communication device resulting from one or more
interfering
transmitters. A device receiving a RUM can reduce it's transmit power by a
predetermined factor, which should reduce interference at the device issuing
the RUM.
To implement fairness, performance metrics of multiple sectors can be compared
to
determine whether one or more sectors are disadvantaged with respect to other
sectors,
or an aggregate of the sectors. Accumulation, issuance, and/or weighting of
RUMs, or
interference avoidance credits in general (including modification of a
sector's own
transmit power), can be adjusted to mitigate disadvantaged sectors (e.g.,
sectors having
a relatively low performance metric) from being excessively hampered by RUMs
issued
from neighboring sectors, or to mitigate non-disadvantaged sectors from
accumulating/issuing an excessive number of RUMs.
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[0038] It should be appreciated that a wireless AN can utilize both reverse
link
(RL) RUMs and forward link (FL)/downlink (DL) RUMs. A FL/DL RUM is a RUM
transmitted by a base station of the wireless AN to interfering ATs. The ATs
receive
the FL RUM and determine whether to obey the RUM, as described in more detail
hereinafter. If the RUM is obeyed, the ATs can reduce power on RL channels,
reducing
interference at the issuing base station (and, e.g., other base stations in a
vicinity of the
AT). In contrast, a RL RUM is issued by an AT (e.g., utilizing a RUM
accumulated by
a serving sector associated with the AT) to one or more neighboring base
stations of the
wireless AN. The base stations determine whether to obey the RL RUM, and can
reduce FL transmission power if the RL RUM is obeyed. As discussed below,
accumulation and/or adjustment of RUM accumulation or issuance rates can apply
to
either or both of DL and FL RUMs
[0039] In a mobile environment, access terminals (ATs) and base stations
increase transmit power at various times based on various factors. For
instance, a base
station might receive a signal from an AT indicating that signals transmitted
by the base
station are received with very low power at the AT. Thus, the base station
might
increase transmit power to improve communication with the AT. Furthermore,
where a
device transmission has low signal to noise ratio (SNR) characteristics at a
receiver, the
transmit power of the signal can be increased. Increased transmit power can
lead to
interference at nearby devices, however. Thus, the RUM provides feedback to a
device
indicating that the transmit power of the device is too high for other nearby
devices.
[0040] RUMs can have drawbacks, however. For instance, a single device can
monopolize sector communication by issuing too many RUMs to nearby devices. If
the
other devices excessively reduce their transmit power based on multiple
received
RUMs, quality of communication of such devices can suffer. Thus, accumulation
and/or issuance of RUMs for a device must be managed so that a few devices do
not
reduce transmission quality for nearby devices. In effect, fairness principles
can be
enforced to provide good overall communication for devices in a wireless AN.
[0041] In one aspect of the disclosure, a number of RUMs that a sector of a
wireless AN can issue at a given time depends on a number of such RUMs that
have
been accumulated for the sector (e.g., in a RUM `token bucket' so to speak,
associated
with the sector). A rate at which the sector accumulates RUMs is termed a RUM
accumulation rate. Accumulated RUMs associated with the sector are decremented
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when the sector issues a RUM (e.g., on behalf of a base station or mobile
device in the
sector). Thus, the RUM accumulation rate can, at least in part, govern a rate
at which
the sector can send out RUMs.
[0042] In at least one aspect of the subject disclosure, accumulation of RUMs
is
determined on a sector-by-sector basis. A rate at which a sector accumulates
RUMs can
be based on a performance metric of the sector in comparison with a like
performance
metric of one or more nearby sectors. The accumulation of RUMs can be
established,
increased and/or decreased based on a comparison of the sector performance
metrics. It
should be appreciated that establishing and/or adjusting RUM accumulation
rates, as
described herein, can apply to either FL or RL RUMs, or both. Further,
performance
metrics can be monitored over time to adjust/maintain RUM accumulation based
on
contemporary changes in the monitored metrics. Thus, the disclosure provides
for
implementing inter-sector fairness based on performance of various sectors of
a mobile
AN.
[0043] In at least one aspect, sector performance metrics can be collected
over a
backhaul network between base stations. In another aspect, the metrics can be
collected
at a designated base station, shared among various base stations, or managed
at a
centralized location (e.g., a centralized component of a radio access network
[RAN], a
component of a mobile back-end network coupled with each of the various base
stations, or the like). According to further aspects, one or more ATs can
collect the
performance metrics from base stations in the wireless AN and forward the
collected
metrics to a serving base station associated with the ATs. For instance, an AT
can
decode the performance metrics over-the-air (OTA) from broadcast transmissions
of
nearby base stations of the wireless AN (e.g., where such broadcast
transmissions have
adequate SNR characteristics at an AT). The AT can then forward the
performance
metric information to a serving base station coupled with the AT.
Alternatively, in
some aspects, the AT can re-transmit and/or forward the broadcast
transmissions to the
serving base station which can decode the performance metrics from the re-
transmitted/forwarded signal.
[0044] In one or more other aspects, sector RUM accumulation rates are
determined based on aggregate sector performance. For instance, a base station
of a
wireless AN can collect performance metric information of neighboring base
stations
from such base stations (e.g., over a backhaul network) and/or from ATs served
by the
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base station of the wireless AN. The collected information can be aggregated
at the
base station (or, e.g., at a central controller of the wireless AN in some
instances) to
provide an aggregate performance metric of a set of base stations of the
wireless AN. A
performance metric of an individual sector (or, e.g., each sector of the
wireless AN) can
then be compared to the aggregate data to determine a degree of disadvantage
of the
individual sector as compared with the aggregated data. The degree of
disadvantage, if
any, can be utilized to establish and/or update a RUM accumulation rate for
the sector.
For instance, the RUM accumulation rate can be increased, decreased or
maintained
based on a sector performance metric as compared with the aggregate data. By
aggregating data of neighboring sectors at an individual sector, variations in
relative
interference as observed at an individual sector can be established.
[0045] According to still other aspects, a rate at which a sector issues RUMs,
or
associates RUMs with ATs within the sector can be based on an aggregate
performance
metric as well. Thus, where a sector has poor median data rates as compared
with an
aggregate of sectors, a RUM accumulation rate and/or issuance rate of that
sector can be
increased. If, at a later time, the sector median data rate improves relative
to the
aggregate sector data, the accumulation/issuance rate can be maintained or
reduced, as
appropriate. Thus, the subject disclosure provides for controlled accumulation
and/or
issuance of RUMs based on sector performance, and further provides a mechanism
to
adjust sector performance by increasing/decreasing rates at which RUMs are
accumulated at various sectors.
[0046] As used in the subject disclosure, the terms "component," "system,"
"module" and the like are intended to refer to a computer-related entity,
either hardware,
software, software in execution, firmware, middle ware, microcode, and/or any
combination thereof. For example, a module can be, but is not limited to
being, a
process running on a processor, a processor, an object, an executable, a
thread of
execution, a program, a device, and/or a computer. One or more modules can
reside
within a process and/or thread of execution and a module can be localized on
one
electronic device and/or distributed between two or more electronic devices.
Further,
these modules can execute from various computer-readable media having various
data
structures stored thereon. The modules can communicate by way of local and/or
remote
processes such as in accordance with a signal having one or more data packets
(e.g.,
data from one component interacting with another component in a local system,
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distributed system, and/or across a network such as the Internet with other
systems by
way of the signal). Additionally, components or modules of systems described
herein
can be rearranged and/or complemented by additional components/modules/systems
in
order to facilitate achieving the various aspects, goals, advantages, etc.,
described with
regard thereto, and are not limited to the precise configurations set forth in
a given
figure, as will be appreciated by one skilled in the art.
[0047] Furthermore, various aspects are described herein in connection with an
access terminal - AT. An AT can also be called a system, a subscriber unit, a
subscriber
station, mobile station, mobile, mobile communication device, mobile device,
remote
station, remote terminal, user terminal (UT), user agent (UA), a user device,
or user
equipment (UE). A subscriber station can be a cellular telephone, a cordless
telephone,
a Session Initiation Protocol (SIP) phone, a wireless local loop (WLL)
station, a
personal digital assistant (PDA), a handheld device having wireless connection
capability, or other processing device connected to a wireless modem or
similar
mechanism facilitating wireless communication with a processing device.
[0048] In one or more exemplary embodiments, the functions described can be
implemented in hardware, software, firmware, middleware, microcode, or any
suitable
combination thereof. If implemented in software, the functions can be stored
on or
transmitted over as one or more instructions or code on a computer-readable
medium.
Computer-readable media includes both computer storage media and communication
media including any medium that facilitates transfer of a computer program
from one
place to another. A storage media may be any physical media that can be
accessed by a
computer. By way of example, and not limitation, such computer storage media
can
comprise RAM, ROM, EEPROM, CD-ROM or other optical disk storage, magnetic
disk storage or other magnetic storage devices, smart cards, and flash memory
devices
(e.g., card, stick, key drive...), or any other medium that can be used to
carry or store
desired program code in the form of instructions or data structures and that
can be
accessed by a computer. In addition, any connection is properly termed a
computer-
readable medium. For example, if the software is transmitted from a website,
server, or
other remote source using a coaxial cable, fiber optic cable, twisted pair,
digital
subscriber line (DSL), or wireless technologies such as infrared, radio, and
microwave,
then the coaxial cable, fiber optic cable, twisted pair, DSL, or wireless
technologies
such as infrared, radio, and microwave are included in the definition of
medium. Disk
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and disc, as used herein, includes compact disc (CD), laser disc, optical
disc, digital
versatile disc (DVD), floppy disk and blu-ray disc where disks usually
reproduce data
magnetically, while discs reproduce data optically with lasers. Combinations
of the
above should also be included within the scope of computer-readable media.
[0049] For a hardware implementation, the processing units' various
illustrative
logics, logical blocks, modules, and circuits described in connection with the
aspects
disclosed herein can be implemented or performed within one or more
application
specific integrated circuits (ASICs), digital signal processors (DSPs),
digital signal
processing devices (DSPDs), programmable logic devices (PLDs), field
programmable
gate arrays (FPGAs), discrete gate or transistor logic, discrete hardware
components,
general purpose processors, controllers, micro-controllers, microprocessors,
other
electronic units designed to perform the functions described herein, or a
combination
thereof. A general-purpose processor can be a microprocessor, but, in the
alternative,
the processor can be any conventional processor, controller, microcontroller,
or state
machine. A processor can also be implemented as a combination of computing
devices,
e.g., a combination of a DSP and a microprocessor, a plurality of
microprocessors, one
or more microprocessors in conjunction with a DSP core, or any other suitable
configuration. Additionally, at least one processor can comprise one or more
modules
operable to perform one or more of the steps and/or actions described herein.
[0050] Moreover, various aspects or features described herein can be
implemented as a method, apparatus, or article of manufacture using standard
programming and/or engineering techniques. Further, the steps and/or actions
of a
method or algorithm described in connection with the aspects disclosed herein
can be
embodied directly in hardware, in a software module executed by a processor,
or in a
combination of the two. Additionally, in some aspects, the steps and/or
actions of a
method or algorithm can reside as at least one or any combination or set of
codes and/or
instructions on a machine-readable medium and/or computer-readable medium,
which
can be incorporated into a computer program product. The term "article of
manufacture" as used herein is intended to encompass a computer program
accessible
from any computer-readable device or media.
[0051] Additionally, the word "exemplary" is used herein to mean serving as an
example, instance, or illustration. Any aspect or design described herein as
"exemplary" is not necessarily to be construed as preferred or advantageous
over other
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14
aspects or designs. Rather, use of the word exemplary is intended to present
concepts in
a concrete fashion. As used in this application, the term "or" is intended to
mean an
inclusive "or" rather than an exclusive "or". That is, unless specified
otherwise, or clear
from context, "X employs A or B" is intended to mean any of the natural
inclusive
permutations. That is, if X employs A; X employs B; or X employs both A and B,
then
"X employs A or B" is satisfied under any of the foregoing instances. In
addition, the
articles "a" and "an" as used in this application and the appended claims
should
generally be construed to mean "one or more" unless specified otherwise or
clear from
context to be directed to a singular form.
[0052] As used herein, the terms to "infer" or "inference" refer generally to
the
process of reasoning about or inferring states of the system, environment,
and/or user
from a set of observations as captured via events and/or data. Inference can
be
employed to identify a specific context or action, or can generate a
probability
distribution over states, for example. The inference can be probabilistic-that
is, the
computation of a probability distribution over states of interest based on a
consideration
of data and events. Inference can also refer to techniques employed for
composing
higher-level events from a set of events and/or data. Such inference results
in the
construction of new events or actions from a set of observed events and/or
stored event
data, whether or not the events are correlated in close temporal proximity,
and whether
the events and data come from one or several event and data sources.
[0053] Referring now to the drawings, Fig. 1 illustrates a wireless
communication system 100 with multiple base stations 110 and multiple
terminals 120,
such as can be utilized in conjunction with one or more aspects. A base
station (110) is
generally a fixed station that communicates with the terminals and can also be
called an
access point, a Node B, or some other terminology. Each base station 110
provides
communication coverage for a particular geographic area or coverage area,
illustrated as
three geographic areas in Fig. 1, labeled 102a, 102b, and 102c. The term
"cell" can
refer to a base station and/or its coverage area depending on the context in
which the
term is used. To improve system capacity, a base station geographic
area/coverage area
can be partitioned into multiple smaller areas (e.g., three smaller areas,
according to cell
102a in Fig. 1), 104a, 104b, and 104c. Each smaller area (104a, 104b, 104c)
can be
served by a respective base transceiver subsystem (BTS). The term "sector" can
refer to
a BTS and/or its coverage area depending on the context in which the term is
used. For
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a sectorized cell, the BTSs for all sectors of that cell are typically co-
located within the
base station for the cell. The RUM accumulation/utilization techniques
described herein
can be used for a system with sectorized cells as well as a system with
multiple un-
sectorized cells (e.g., a plurality of cells of a larger geographic area). For
simplicity, in
the following description, unless specified otherwise, the term "base station"
is used
generically for a fixed station that serves a sector as well as a fixed
station that serves a
cell. In addition, the term "wireless AN" is used generically to refer to a
geographic cell
comprising multiple sectors, or a geographic area comprising multiple cells.
[0054] Terminals 120 are typically dispersed throughout the system, and each
terminal 120 can be fixed or mobile. Terminals 120 can also be called a mobile
station,
user equipment, a user device, or some other terminology, as discussed above.
A
terminal 120 can be a wireless device, a cellular phone, a personal digital
assistant
(PDA), a wireless modem card, and so on. Each terminal 120 can communicate
with
zero, one, or multiple base stations 110 on the downlink and uplink at any
given
moment. The downlink (or forward link) refers to the communication link from
the
base stations to the terminals, and the uplink (or reverse link) refers to the
communication link from the terminals to the base stations. As used herein, a
base
station with which a terminal 120 maintains an active communication or an
active
registration is termed a "serving base station".
[0055] For a centralized architecture, a system controller 130 couples to base
stations 110 and provides coordination and control for base stations 110. For
instance,
as discussed herein, the system controller can facilitate obtaining
performance metric
data for multiple base stations 110, aggregating the data, and providing RUM
accumulation information based on the aggregate data. For a distributed
architecture,
base stations 110 can communicate with one another as needed (e.g., employing
a
backhaul network, not depicted). Data transmission on the forward link often
occurs
from one access point to one access terminal at or near the maximum data rate
that can
be supported by the forward link and/or the communication system. Additional
channels of the forward link (e.g., control channel) can be transmitted from
multiple
access points to one access terminal. Reverse link data communication can
occur from
one access terminal to one or more access points.
[0056] Fig. 2 is an illustration of an ad hoc or unplanned/semi-planned
wireless
communication environment 200, in accordance with various aspects. System 200
can
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comprise one or more base stations 202 in one or more cells and/or sectors
that receive,
transmit, repeat, etc., wireless communication signals to each other and/or to
one or
more mobile devices 204. As illustrated, each base station 202 can provide
communication coverage for a particular geographic area, illustrated as four
geographic
areas, labeled 206a, 206b, 206c and 206d. Each base station 202 can comprise a
transmitter chain and a receiver chain, each of which can in turn comprise a
plurality of
components associated with signal transmission and reception (e.g.,
processors,
modulators, multiplexers, demodulators, demultiplexers, antennas, and so
forth.), as will
be appreciated by one skilled in the art. Mobile devices 204 can be, for
example,
cellular phones, smart phones, laptops, handheld communication devices,
handheld
computing devices, satellite radios, global positioning systems, PDAs, and/or
any other
suitable device for communicating over wireless network 200. System 200 can be
employed in conjunction with various aspects described herein in order to
facilitate
providing a wireless communication environment (200), as set forth herein.
[0057] Fig. 3 illustrates a block diagram of an example system 300 that
provides
performance based RUM accumulation for various sectors of a mobile AN 306. A
RUM accumulation apparatus 302 can be coupled with base stations 306A, 306B,
providing management of RUMs for sectors and devices (304) coupled with such
base
stations 306A, 306B. One or more performance metrics of the sectors (306A,
306B)
can be determined and RUM accumulation for each sector can be based on a
comparison of the metric for that sector with at least one other sector.
Accordingly,
RUM accumulation can be managed to provide inter-sector fairness of the mobile
AN
306.
[0058] RUM accumulation apparatus 302 can comprise a data collector 308 that
obtains a performance metric for a sector of a mobile AN 306A and at least one
neighboring sector 306B. The performance metric can comprise various suitable
quality
of service parameters associated with wireless communication. Example
performance
metrics can include median data rate, average data rate, interference level,
SNR, ratio of
guaranteed bit rate to median/average bit rate, achieved packet delay,
achieved packet
delay as compared to a target or guaranteed packet delay, and/or the like or a
combination thereof. The performance metric(s) for a sector (306A, 306B) can
be
calculated and obtained from a base station 306A, 306B serving the sector
(306A,
306B), or from a mobile device 304 communicating with such base station 306A,
306B.
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The performance metric(s) data can be forwarded to the data collector 308 via
a
communication link coupling the RUM accumulation apparatus with the base
stations
306A, 306B and/or a wireless link with the mobile device 304.
[0059] RUM accumulation apparatus 304 can further comprise a management
module 310 that establishes a rate at which devices (304) within a sector
(306A, 306B)
accumulate RUMs. The established RUM accumulation rate(s) can be based on a
comparison of a performance metric pertinent to a particular sector (e.g.,
306A) as
compared with a like performance metric pertinent to at least one additional
sector (e.g.,
306B), or aggregated performance metric data from multiple sectors. As a more
particular example, a median data rate pertaining to sector A (306A) served by
base
station 306A can be forwarded to the data collector 308. Further, a median
data rate
pertaining to sector B (306B) served by a neighboring base station 306B can be
forwarded to data collector 308. A RUM accumulation rate for sector 306A and
related
devices (304) can be based at least in part on a comparison of the median data
rate of
sector A as compared with a median data rate of sector B. According to some
aspects,
the RUM accumulation rate can be updated based on a further such comparison,
for
instance that is determined at periodic times, after a threshold change is
detected in the
performance metric(s) of the respective sectors (306A, 306B), and/or the like
or a
combination thereof.
[0060] Data collected by data collector 308 can be stored in memory 312
(which, e.g., can comprise any suitable form of electronic and/or magnetic
storage
media such as disk drives, optical discs, flash memory, random access memory,
and/or
the like). Further, results of performance metric comparisons conducted by
management module 310 can be stored in memory 312 for reference. For instance,
when determining whether to update a determined RUM accumulation rate based on
changes in a performance metric(s), the results or prior RUM accumulation
rate(s) can
be obtained from memory 312. Rum accumulation apparatus 302 further comprises
a
processor 314 configured to execute instructions on data stored in memory 312
pertinent
to processes of the RUM accumulation apparatus 302 (e.g., data collection and
storage
in memory, parsing metrics v. sectors, comparing metrics for one sector v. one
or more
other sectors, determining RUM accumulation rates based on such comparisons,
updating RUM accumulation rates, and so on).
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[0061] It should be appreciated that any number of base stations 306A, 306B
can be included in the radio access network (RAN) 306 of system 300. Base
stations
306A, 306B can include various wireless transmitters including cellular
transceivers,
wireless fidelity (WiFi) transmitters, microwave frequency transmitters (e.g.,
worldwide
interoperability for microwave access [WiMAX]), and/or the like, coupled to a
common
wireless mobile RAN site 306. Thus, various cellular, mobile communication,
and like
access technologies can be included in the mobile RAN site of 306.
[0062] Fig. 4 illustrates a block diagram of an example RUM management
apparatus 402 according to one or more aspects of the subject disclosure.
Apparatus
402 can be coupled with a centralized controller of a RAN (e.g., see system
controller
130 of Fig. 1, supra), or can be distributed across one or more base stations
of the RAN
(e.g., base stations 306A, 306B of Fig. 3, supra or backhaul network 506 of
Fig. 5,
infra). The apparatus 402 can obtain performance metrics of wireless
communications
provided by such base stations, aggregate the data, and determine and update
sector
RUM accumulation rates based on sector metrics compared with aggregate metric
data.
Accordingly, system 400 provides a fairness-based RUM accumulation technique
that
can determine a desirable communication metric and optimize overall operation
of the
RAN based on changing communication metric levels.
[0063] RUM management apparatus 402 can comprise an accumulation
apparatus 406 that receives data via a communication interface 404 with
components of
a RAN (e.g., base stations). The accumulation apparatus 406 comprises a data
collector
410 that obtains performance metric data pertaining to sectors of the RAN, and
a
management module 412 that determines a RUM accumulation rate for sectors of
the
RAN, based on comparison of a sector performance metric with a performance
metric
of at least one other sector. Thus, apparatus 402 can provide fairness-based
sector RUM
accumulation rates based on desirable metrics pertinent to wireless
communication.
Thus, sectors exhibiting poor metrics can be given a higher RUM accumulation
rate,
resulting in more RUMs issued to devices of the poor sector. Sectors
exhibiting
relatively strong metrics can be given a lower RUM accumulation rate,
resulting in
fewer RUMs issued to devices of the strong sectors. Thus, by having more RUMs,
the
poor metric sectors can more readily reduce transmission power of neighboring
interfering transmitters. Likewise, the strong metric sectors have a lesser
ability to
reduce transmission power of neighboring transmitters. Such an arrangement
provides a
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19
significant benefit. First, devices that most need to reduce power of
interfering
transmissions are given a greater opportunity to do so. Further, devices that
have little
need to reduce power of interfering transmissions have a lesser opportunity to
do so.
Where a poor sector neighbors a strong sector, it is significant that the poor
sector be
able to reduce transmission power of the neighboring sector, while avoiding
significant
reduction of its own signal power by RUMs issued to the strong sector.
[0064] RUM management apparatus 402 can further comprise a RUM control
apparatus 408. The control apparatus 408 can establish rates for devices to
issue
accumulated RUMs based on inter-sector performance metrics. Further, the
control
apparatus 408 can manage RUM accumulation rates based on changing sector
performance metrics; accumulation rates can be updated based on changing
disparities
in a sector's performance metric(s) as compared with metrics of neighboring
sectors.
[0065] Control apparatus 408 can comprise an implementation module 420 that
establishes a rate that devices of a sector can issue accumulated RUMs. The
issuance
rate can be determined in addition to accumulation rates determined by the RUM
accumulation apparatus 406. Thus, a device can accumulate a number of RUMs
over
time, but can be limited in how quickly it can utilize those RUMs. Therefore,
if a
performance metric for the device suddenly changes dramatically for the worse,
the
device's ability to issue many accumulated RUMs in a short period of time,
which can
significantly degrade performance of nearby devices, can be modulated at least
by the
number of RUMs accumulated for a sector serving the device. In at least one
other
aspect, RUM issuance can further be limited by a max RUM issuance rate. In yet
other
aspects, the RUM issuance rate can depend on a degree of disadvantage of the
sector.
In at least one aspect, RUM issuance can be modulated by a combination of the
foregoing or like mechanisms.
[0066] As discussed above, RUM issuance rates can be a predetermined rate
and/or sector-specific rate established based on performance metric
comparisons similar
to those determined by management module 412 for establishing accumulation
rates
(e.g., that establish a degree of disadvantage of a sector as compared with
other sectors).
In one or more aspects, the issuance rate is modulated by an associated RUM
accumulation rate (e.g., of RUMs of unit weight, or in other aspects,
modulation can
include weights of weighted RUMs) for a sector serving a device. In such
aspects, the
implementation module 420 can optionally determine whether a terminal within
the
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sector sends a RUM based on the RUM accumulation rate, RUM issuance rate,
comparison of performance metrics, sector disadvantage, or a combination of
these
and/or like factors.
[0067] Control apparatus 408 can further comprise a priority adjustment module
418 that can update RUM accumulation rates of sectors of a RAN. Rate updates
can be
based at least in part on current performance metric comparisons for such
sectors as
compared with one or more neighboring sectors. The following example is
provided to
illustrate one aspect in which RUM accumulation rates can be determined; it
should not
be construed as limiting however. Rather, other mechanisms for updating RUM
accumulation rates based on performance metrics of multiple sectors of a RAN
known
by those of skill in the art or made known to those of skill in the art by way
of the
context provided herein, are included herein as part of the subject
disclosure.
[0068] For purposes of the following example, the following quantities are
defined:
mi (k) = median performance metric of ATs of sector i at epoch k
r (k) = rate of RUM accumulation at sector i at epoch k
Mi (k) = Median of m1 (k) V j that are neighbors of i , including i
At the end of a RUM rate adaptation epoch (k) (e.g., a period of time at the
end of which
the priority adjustment module 418 determines updated RUM rates) a sector can
update
r for epoch (k+1) (or, e.g., leave r substantially unchanged where suitable).
The
updated r is stored in memory 416 and can be utilized to generate RUMs at a
modified
rate by processor 414 during epoch (k+1). RUM accumulation rate adaptation can
be
based on fairness criteria utilizing a comparison of a sector's performance
compared
with an aggregate performance data of one or all other sectors j, including
the sector i in
at least some embodiments. The following algorithms provide one mechanism for
updating r based on inter-sector fairness:
If mi (k) < Mi (k) t h e n r (k + 1) = r (k) + A . (k) (where A i (k) is a
positive
quantity)
If mi (k) >- Mi (k) then r (k + 1) = r (k) - 0 i (k) (where 0 i (k) is a
positive
quantity)
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Thus, where a median performance metric (e.g., data rate) of a sector mi (k)
is less than
the median performance metric of a plurality of sectors Mi (k) (e.g., all
sectors j
including sector i), the RUM accumulation rate of sector i r can be increased
by a
positive amount. In contrast, where the median performance metric of sector i
is less or
equal to the median performance metric of the plurality of sectors, the RUM
accumulation rate of sector i can be decreased by a positive amount. Further
to the
above, the RUM accumulation rate can be limited by maximum and/or minimum
accumulation rates. The maximum rate can be determined to prevent a
disadvantaged
sector from excessively degrading neighboring sectors. The minimum rate, on
the other
hand, enables a sector to serve a few users seeing excessive interference even
though the
sector as a whole is not disadvantaged with respect to neighboring sectors.
Further, the
minimum and maximum accumulation rates can be established based on a degree of
sector disadvantage as compared with neighboring sectors, as described herein.
[0069] According to one or more additional aspects of the subject disclosure,
priority adjustment module 418 can update a RUM accumulation rate of a sector
by a
constant amount, or a variable amount. The constant amount can be
predetermined
based on various wireless characteristics of a mobile RAN site (e.g.,
interference, multi-
path scattering). It should be appreciated that the wireless characteristics
can be
updated at various points in time, and utilized to modify the constant amount.
The
variable amount can be based on the various factors present during one or more
epochs
near in time to a particular epoch (e.g., a state of factors during the epoch
k can be
employed, an aggregated state of factors during epoch k and/or one or more
prior epochs
k-2, k-1, or the like). The various factors can include the performance metric
of a sector
or of one or more neighboring sectors, various wireless characteristics
discussed above
with respect to the constant amount, or a combination thereof or of the like.
Accordingly, a RUM accumulation rate can be adjusted varying amounts. As an
example, if a sector is significantly poorer than its neighboring sectors, a
corresponding
RUM accumulation rate can be increased a relatively large amount.
[0070] According to one or more other aspects, RUM management apparatus
402 can further comprise a priority module 422 and a request parser 424.
Priority
module 422 can establish a weight of a RUM issued by devices within the
sector. The
weight can be based at least in part on a current RUM accumulation rate for
that sector.
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The weight can be utilized by receiving transmitters to determine whether the
RUM
should be obeyed or ignored (e.g., based on performance metric(s) of a sector
associated
with the receiving transmitters). RUM request parser 424 can employ the RUM
accumulation rate to determine priority of a RUM received by a particular
transmitter
(e.g., a base station, an AT). Priority of the RUM can be based at least in
part on the
RUM accumulation rate of the receiving transmitter, analogous to the RUM
weight
discussed above. Thus, RUM request parser 424 can determine whether a RUM
should
be obeyed or ignored by a receiving transmitter based on the priority.
[0071] Fig. 5 depicts a block diagram of a system 500 that provides RUM
management for a mobile AN according to aspects disclosed herein. System 500
can
comprise a mobile device 502 coupled with base stations 506A, 506B, 506C, 506D
of a
RAN. Furthermore, the base stations are coupled to a backhaul network 506, by
which
the base stations can exchange data. A RUM accumulation apparatus 508 is
coupled
with the backhaul network. In one aspect, performance metric data for various
sectors
of the RAN are determined and shared among the base stations 506A, 506B, 506C,
506D via the backhaul network 506. In another aspect, performance metric data
for the
various sectors can be uploaded to the RUM accumulation apparatus 508 from the
base
stations 506A, 506B, 506C, 506D. According to still other aspects, performance
metrics can be determined from OTA messages received at mobile devices 502
within
the sectors. The mobile devices can analyze the OTA messages to determine
performance metrics of such messages. Such metrics can then be provided to the
RAN
and base stations 506A, 506B, 506C, 506D and/or to the RUM accumulation
apparatus
508 by way of such base stations 506A, 506B, 506C, 506D.
[0072] RUM accumulation apparatus 508 can determine RUM accumulation
rates for sectors (506A, 506B, 506C, 506D) of the RAN, and distribute the RUMs
to
those sectors for utilization by devices of such sectors. In another aspect,
the RUM
accumulation rates for each sector can be determined by base stations 506A,
506B,
506C, 506D associated with such sectors. Accumulated RUMs can be distributed
to
mobile devices 502 once accumulated.
[0073] A RUM management module 504 coupled with a mobile device 502 can
modulate a rate at which RUMs are issued to other devices in nearby sectors
(506A,
506B, 506C, 506D). An issuance rate for a mobile device 502 can determine how
often
the device 502 can send accumulated RUMs. Issuance rates can be determined
based on
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performance metrics of wireless transmissions in the sectors, determined as
described
above. Further, the RUM accumulation rates and/or RUM issuance rates can be
updated
based on changes in the metrics as described herein. Accordingly, system 500
provides
a fairness-based mechanism for accumulating RUMs and issuing RUMs, utilizing
performance metrics of a sector as compared with one or more neighboring
sectors.
[0074] Fig. 6 illustrates a block diagram of a system 600 comprising a sample
base station 602 that provides RUM accumulation management based on
performance
metrics of sectors of a RAN. In at least one aspect of the subject disclosure,
base station
602 can determine performance metrics based on wireless transmissions
particular to a
sector of the RAN. Furthermore, base station 602 can provide paging functions
for the
mobile network with respect to mobile devices 604 within a geographic area
served by
the network (e.g., see Figs. 1 and 2). The base station 602 can continue
broadcasting
paging signals until a response is received by a target mobile device, a
paging
termination command is received from the mobile network, or an expiration
timer
maintained by the base station 602 expires, or a combination thereof. In
accordance
with particular aspects, base station 602 can maintain a registration counter
for the
mobile device with respect to a tracking/location area served by the base
station 602.
Further, the registration counter can be maintained even though a mobile
device fails to
respond to a paging event. Accordingly, system 600 facilitates inter-system
mobility by
paging devices 604 independently of other systems (not depicted), and
maintaining
device registration in spite of a failed paging response (e.g., where the
mobile device
responds to the other system's page).
[0075] Base station 602 (e.g., access point, ...) can comprise a receiver 610
that
receives signal(s) from one or more mobile devices 604 through a plurality of
receive
antennas 606, and a transmitter 632 that transmits signals to the one or more
mobile
devices 604 through a transmit antenna(s) 608. Receiver 610 can receive
information
from receive antennas 606 and can further comprise a signal recipient (not
shown) that
receives uplink data transmitted by mobile device(s) 604. Additionally,
receiver 610 is
operatively associated with a demodulator 612 that demodulates received
information.
Demodulated symbols are analyzed by a processor 614, which also provides
symbols to
a modulator 630 for transmission. Processor 614 is coupled to a memory 616
that stores
information related to functions provided by base station 602. In one
instance, stored
information can comprise protocols for obtaining and/or determining
performance
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metrics of wireless communications with mobile devices 604. Particularly, the
stored
information can comprise rules for determining or updating RUM accumulate
rates as
well as RUM issuance rates for such devices 604, depending on the performance
metrics as compared with like metrics associated with a neighboring base
station(s).
[0076] Processor 614 is further coupled to a data collector that can obtain
performance metric information pertinent to base station 602 and at least one
neighboring base station (not depicted). Information collected at data
collector 618 can
be stored in memory 616 for access by other components (612, 614, 620, 622,
624, 626,
628, 630) of base station 602. A management module 620 can establish a rate at
which
the mobile devices 604 within a sector served by base station 602 (and, e.g.,
communicatively coupled with) accumulate RUMs. The accumulation rate can be
based on a comparison of the performance metrics associated with base station
602 as
compared with the at least one other neighboring base stations, as described
herein.
Accumulation rates can be stored in memory 616 to be referenced by other
components
(612, 614, 620, 622, 624, 626, 628, 630) of the base station 602.
[0077] A priority adjustment module 622 can update RUM accumulation rates
based on subsequent performance metrics base station 602 communications. Thus,
if a
median data rate for devices 604 coupled with base station 602 decreases as
compared
with median data rates for neighboring sectors, the priority adjustment module
602 can
increase RUM accumulation rate for such devices 604. It should be appreciated
that the
foregoing example is only one mechanism for updating accumulation rate, and
the
subject disclosure should not be construed as limited to such example. Rather,
other
examples provided herein, examples known to one of skill in the art or made
known to
one of skill in the art by way of the context provided herein, are
incorporated into the
subject disclosure.
[0078] In addition to the foregoing, an implementation module 624 can
determine a rate that devices 604 can send or issue accumulated RUMs. The
issuance
rate can be determined on various factors, including the RUM accumulation rate
of the
sector, number of devices 604 operating within the sector, one or more sector
performance metrics, or a combination thereof or of the like. According to
some
aspects, the implementation module 624 can modulate the rate that devices 604
issue
RUMs with the rate the sector accumulates RUMs (e.g., where the modulation can
incorporate a weight of a RUM or can be of unit weight). In at least on other
aspect,
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implementation module 624 can determine whether a terminal within a sector
served by
base station 602 sends a RUM based at least in part on the RUM accumulation
rate
and/or RUM issuance rate.
[0079] Base station 602 can further comprise a RUM request parser 626 that
determines priority of a RUM received by a mobile device 604 from a
neighboring
sector. The priority can be established based on the RUM accumulation rate and
a
corresponding rate and/or performance metric of the other sector.
Additionally, base
station 602 can comprise a priority module 628 that adjusts a weight of a RUM
issued
or sent by devices 604 in the sector based at least in part on the RUM
accumulation rate.
Accordingly, neighboring devices that receive the RUM can determine whether to
obey
the issued RUM based at least in part on the weight. Optionally, where a RUM
is of
unit weight, it must be obeyed by all such neighboring devices.
[0080] Fig. 7 illustrates a block diagram of an example system 700 that
comprises a mobile device 702. Mobile device 702 can be configured to
wirelessly
couple with one or more base stations 704 and affiliated mobile networks (not
depicted).
Mobile device 702 can additionally be configured to obtain performance metrics
of
nearby base stations and transmit the metrics to a serving base station 704,
as described
herein.
[0081] Mobile device 702 includes at least one antenna 706 (e.g., a
transmission
receiver or group of such receivers comprising an input interface) that
receives a signal
(e.g., a wireless signal, such as an OTA message) and receiver(s) 708, which
performs
typical actions (e.g., filters, amplifies, down-converts, etc.) on the
received signal.
According to at least some aspects, processor(s) 712 can analyze signals
received from
demodulator(s) 710 and obtain wireless performance metrics of such signals. In
general, antenna 706 and transmitter 726 (collectively referred to as a
transceiver) can
be configured to facilitate wireless data exchange with base station(s) 704.
[0082] Antenna 706 and receiver(s) 708 can also be coupled with the
demodulator(s) 710 that can demodulate received symbols and provide them to
the
processor(s) 712 for evaluation. In some aspects, receiver 708 can receive OTA
transmissions from base stations (704). In a particular example, the receiver
708 can
obtain OTA transmissions from a neighboring base station (e.g., as part of
broadcast
signals from such base station) comprising a performance metric of the
neighboring
base station. The OTA message can be analyzed at mobile device 702 and/or
forwarded
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to base station 704 for analysis. Additionally, receiver 708 can obtain a
second OTA
message from the neighboring base station comprising a RUM, requiring the
mobile
device 702 to reduce power at the transmitter 726.
[0083] It should be appreciated that processor(s) 712 can control and/or
reference one or more components (706, 708, 710, 714, 716, 724, 726) of the
mobile
device 702. Further, processor(s) 712 can execute one or more modules,
applications,
engines, or the like (716, 718, 720, 722) that comprise information or
controls pertinent
to executing functions of the mobile handset 702. For instance, such functions
can
include conducting wireless communications with remote devices (704),
receiving OTA
messages, analyzing such messages, determining wireless performance metrics of
wireless transmissions, receiving and processing RUMs, or the like, as
described herein.
[0084] Mobile handset 702 can additionally include memory 714 that is
operatively coupled to processor(s) 712. Memory 714 can store data to be
transmitted,
received, and the like, and instructions suitable to conduct wireless
communication with
remote device (704). Further, memory 716 can store the modules, applications,
engines,
etc. (718, 720, 722) executed by processor(s) 714, above.
[0085] In some aspects of the disclosure, mobile device 702 can comprise an
analysis module 716 that determines performance metrics (e.g., average or
median data
rate, interference, SNR, etc.) of wireless signals received at the mobile
device 702.
Furthermore, a routing module 718 can wirelessly transmit performance metrics
of one
or more OTA messages obtained at receiver 708 to a base station 704 serving
the mobile
device 702. Based at least in part on a value of the performance metric, the
serving base
station 702 can send a message to the mobile device 704 that includes a RUM.
The
RUM can be issued to mobile device 702 for use by such device 702 in managing
nearby transmitter power, or can be a similar such message sent to mobile
device 702 to
reduce power at transmitter 726.
[0086] According to particular aspects of the disclosure, mobile device 702
can
comprise a priority module 720 that identifies and processes a weighting
factor for a
received RUM. In addition, the priority module 720 can determine a weighting
factor
for a RUM issued for use by the mobile device 702. In either case, weighting
can be
determined at least in part by a RUM accumulation rate associated with a
sector serving
the mobile device 702. An arbitration component 722 can instruct processor 712
to
obey a DL RUM (e.g., pertaining to RL data transmitted by the mobile device
702)
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based on a comparison of a weighting factor of the DL RUM and a performance
metric
of the sector. Arbitration rules stored in memory 714 can determine when the
DL RUM
should be obeyed based on such comparison.
[0087] The aforementioned systems have been described with respect to
interaction between several components, modules and/or communication
interfaces. It
should be appreciated that such systems and components/modules/interfaces can
include
those components or sub-components specified therein, some of the specified
components or sub-components, and/or additional components. For example, a
system
could include a RUM accumulation apparatus 302, RUM control apparatus 408, and
RUM management module 504, or a different combination of these and other
components. Sub-components could also be implemented as components
communicatively coupled to other components rather than included within parent
components. Additionally, it should be noted that one or more components could
be
combined into a single component providing aggregate functionality. For
instance, data
collector 308 can include memory 312, or vice versa, to facilitate receiving
performance
metrics of wireless communications and storing the received metric information
by way
of a single component. The components may also interact with one or more other
components not specifically described herein but known by those of skill in
the art.
[0088] Furthermore, as will be appreciated, various portions of the disclosed
systems above and methods below may include or consist of artificial
intelligence or
knowledge or rule based components, sub-components, processes, means,
methodologies, or mechanisms (e.g., support vector machines, neural networks,
expert
systems, Bayesian belief networks, fuzzy logic, data fusion engines,
classifiers...).
Such components, inter alia, and in addition to that already described herein,
can
automate certain mechanisms or processes performed thereby to make portions of
the
systems and methods more adaptive as well as efficient and intelligent.
[0089] In view of the exemplary systems described supra, methodologies that
may be implemented in accordance with the disclosed subject matter will be
better
appreciated with reference to the flow charts of FIGs. 8-10. While for
purposes of
simplicity of explanation, the methodologies are shown and described as a
series of
blocks, it is to be understood and appreciated that the claimed subject matter
is not
limited by the order of the blocks, as some blocks may occur in different
orders and/or
concurrently with other blocks from what is depicted and described herein.
Moreover,
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not all illustrated blocks may be required to implement the methodologies
described
hereinafter. Additionally, it should be further appreciated that the
methodologies
disclosed hereinafter and throughout this specification are capable of being
stored on an
article of manufacture to facilitate transporting and transferring such
methodologies to
computers. The term article of manufacture, as used, is intended to encompass
a
computer program accessible from any computer-readable device, device in
conjunction
with a carrier, or storage medium.
[0090] Fig. 8 depicts a flowchart of an example methodology 800 that provides
inter-sector fairness in reduction of interference for mobile communications.
At 802,
method 800 can obtain a performance metric of at least two mobile base
stations. The
performance metric can be pertinent to quality of wireless communications
associated
with the two mobile base stations. As specific examples, the performance
metric can
comprise median data rate, average data rate, signal interference, SNR,
percentage of a
guaranteed bit rate satisfied, or a like metric of wireless signals, or a
combination
thereof.
[0091] In one or more aspects, the at least two mobile base stations can be
neighboring base stations of a mobile RAN site. In such circumstance, the
wireless
transmissions of the base stations can often interfere with each other at
receiving
devices. Performance metrics of such signals can be determined at the
receiving
devices and transmitted back to the base stations. In another aspect, the
performance
metrics can be obtained from uplink signals received at the base stations from
the
wireless devices (e.g., the metrics can be specified within the uplink
signals, or the
uplink signals themselves can be analyzed to determine performance metrics of
such
signals). Performance metric information can be shared among the base
stations,
aggregated at a common control device, and/or shared with the mobile devices
for
further analysis.
[0092] At 804, method 800 can determine a RUM accumulation rate for devices
within a sector of the mobile RAN site. The rate can be based at least in part
on a
comparison of the performance metrics of the at least two base stations. As a
particular
example to illustrate the foregoing, an average data rate of a sector can be
compared
with an average data rate of a neighboring sector(s). The RUM accumulation
rate can
then be established based on this comparison. In one particular aspect, the
performance
metric data for all sectors can be aggregated to form aggregate sector
performance
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metric data. A RUM accumulation rate for each sector can be based on a
comparison of
the performance metric for each sector with the aggregate sector performance
metric
data. Accordingly, method 800 provides an algorithm to establish RUM
accumulation
based on wireless communication performance relationships among sectors of a
mobile
RAN site. By way of such algorithm, a likelihood that performance of a sector
is
improved at the expense of a poorly performing sector can be reduced,
providing
increased reliability for mobile communications.
[0093] Fig. 9 illustrates a flowchart of an example methodology 900 that can
manage RUM accumulation rates of sectors of a mobile RAN site to provide inter-
sector
fairness for the site. At 902, method 900 can obtain a performance metric of
at least two
mobile base stations. At 904, method 900 can determine a RUM accumulation rate
for
sectors of the mobile RAN site served by each of the at least two base
stations. At 906,
method 900 can determine a RUM issuance rate for devices of each sector based
at least
in part on the RUM accumulation rate. Thus, a frequency with which a
particular
device (or, e.g., an aggregate of devices) can issue RUMs can be determined
utilizing
the accumulation rate. Other factors determining the issuance rate can include
number
of devices in the sector, performance metrics associated with the particular
device as
compared with the other devices of the sector, type of call the particular
device is
engaged in (e.g., high quality of service calls can be given a higher issuance
rate to
maintain performance of such calls, low quality of service calls can be given
a lower
issuance rate since quality doesn't have as much of a relative impact, and so
on), or the
like or a combination thereof.
[0094] At 908, method 900 can obtain changes in the performance metrics. For
instance, the performance metrics can be re-evaluated at a subsequent point in
time. As
a particular example, the performance metrics can be re-evaluated
periodically. Current
performance metrics (or, e.g., changes in the current metrics as compared with
prior
metrics) can be utilized to re-evaluate the RUM accumulation rates. At 910,
method
900 can update the accumulation rate of sectors of the mobile RAN site based
on a
comparison of sector performance with an aggregate sector performance metric.
Thus,
if a sector performance metric is lower than the aggregate performance metric
(or, e.g.,
less than the aggregate performance metric by a threshold amount), a RUM
accumulation rate of such sector can be increased. Where the sector
performance metric
is greater than the aggregate performance metric (or, e.g., greater than the
aggregate
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performance metric plus a threshold amount), the RUM accumulation rate of the
sector
can be decreased. Where the sector performance metric is substantially
equivalent to
the aggregate performance metric, the RUM accumulation rate can be increased,
decreased, or left unchanged. In addition to the foregoing, changes in sector
performance metric can be based on a constant quantity (e.g., determined based
on prior
RUM accumulation rates, wireless conditions of the mobile RAN site, time-
averaged
statistics of the mobile RAN site, or the like), or based on a variable
quantity
determined at least in part by the RUM accumulation rate, a disparity in the
performance metric of the sector as compared with at least one neighboring
sector (e.g.,
the aggregate performance sector), or the like, or a combination thereof.
[0095] At 912, method 900 can establish a sector priority based on
accumulation
rate. The sector priority can be utilized to determine whether a RUM
accumulation rate
received at a device of the sector is to be obeyed by the receiving device.
The priority
can be based at least in part on a RUM accumulation rate of the sector.
Alternatively, or
in addition, the priority can be based on a weight of the received RUM. At
914, method
900 can establish a weight for a RUM issued by a device of the sector based at
least in
part on the performance metric of the sector, or the RUM accumulation rate. At
916, a
device is instructed to obey a received RUM based on the sector priority, a
weight of the
RUM, or both.
[0096] Fig. 10 illustrates a flowchart of an example methodology 1000 that
facilitates inter-sector fairness for a mobile RAN site. At 1002, method 1000
can obtain
a base station performance metric from an OTA transmission originated from the
base
station. At 1004, method 1000 can forward the performance metric to a serving
base
station. At 1006, method 1000 can receive a RUM based at least in part on the
performance metric. At 1008, method 1000 can obey the RUM based on a weight of
the
RUM, or a performance metric of a serving sector, or both. Obeying the RUM can
further comprise reducing power of wireless transmissions. At 1010, method
1000 can
analyze a sector performance metric of the serving sector. The analysis can be
pertinent
to a received OTA message from the serving base station. At 1012, method 1000
can
accumulate RUMs based at least in part on the sector performance metric as
compared
with an aggregate sector performance metric, where the aggregate sector
performance
metric comprises at least information pertinent to the base station.
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[0097] Fig. 11 depicts a block diagram of an example system 1100 that can
facilitate wireless communication according to some aspects disclosed herein.
On a
downlink, at access point 1105, a transmit (TX) data processor 1110 receives,
formats,
codes, interleaves, and modulates (or symbol maps) traffic data and provides
modulation symbols ("data symbols"). A symbol modulator 1115 receives and
processes the data symbols and pilot symbols and provides a stream of symbols.
A
symbol modulator 1120 multiplexes data and pilot symbols and provides them to
a
transmitter unit (TMTR) 1120. Each transmit symbol can be a data symbol, a
pilot
symbol, or a signal value of zero. The pilot symbols can be sent continuously
in each
symbol period. The pilot symbols can be frequency division multiplexed (FDM),
orthogonal frequency division multiplexed (OFDM), time division multiplexed
(TDM),
code division multiplexed (CDM), or a suitable combination thereof or of like
modulation and/or transmission techniques.
[0098] TMTR 1120 receives and converts the stream of symbols into one or
more analog signals and further conditions (e.g., amplifies, filters, and
frequency
upconverts) the analog signals to generate a downlink signal suitable for
transmission
over the wireless channel. The downlink signal is then transmitted through an
antenna
1125 to the terminals. At terminal 1130, an antenna 1135 receives the downlink
signal
and provides a received signal to a receiver unit (RCVR) 1140. Receiver unit
1140
conditions (e.g., filters, amplifies, and frequency downconverts) the received
signal and
digitizes the conditioned signal to obtain samples. A symbol demodulator 1145
demodulates and provides received pilot symbols to a processor 1150 for
channel
estimation. Symbol demodulator 1145 further receives a frequency response
estimate
for the downlink from processor 1150, performs data demodulation on the
received data
symbols to obtain data symbol estimates (which are estimates of the
transmitted data
symbols), and provides the data symbol estimates to an RX data processor 1155,
which
demodulates (i.e., symbol demaps), deinterleaves, and decodes the data symbol
estimates to recover the transmitted traffic data. The processing by symbol
demodulator
1145 and RX data processor 1155 is complementary to the processing by symbol
modulator 1115 and TX data processor 1110, respectively, at access point 1105.
[0099] On the uplink, a TX data processor 1160 processes traffic data and
provides data symbols. A symbol modulator 1165 receives and multiplexes the
data
symbols with pilot symbols, performs modulation, and provides a stream of
symbols. A
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transmitter unit 1170 then receives and processes the stream of symbols to
generate an
uplink signal, which is transmitted by the antenna 1135 to the access point
1105.
Specifically, the uplink signal can be in accordance with SC-FDMA requirements
and
can include frequency hopping mechanisms as described herein.
[00100] At access point 1105, the uplink signal from terminal 1130 is received
by
the antenna 1125 and processed by a receiver unit 1175 to obtain samples. A
symbol
demodulator 1180 then processes the samples and provides received pilot
symbols and
data symbol estimates for the uplink. An RX data processor 1185 processes the
data
symbol estimates to recover the traffic data transmitted by terminal 1130. A
processor
1190 performs channel estimation for each active terminal transmitting on the
uplink.
Multiple terminals can transmit pilot concurrently on the uplink on their
respective
assigned sets of pilot subbands, where the pilot subband sets can be
interlaced.
[00101] Processors 1190 and 1150 direct (e.g., control, coordinate, manage,
etc.)
operation at access point 1105 and terminal 1130, respectively. Respective
processors
1190 and 1150 can be associated with memory units (not shown) that store
program
codes and data. Processors 1190 and 1150 can also perform computations to
derive
frequency and impulse response estimates for the uplink and downlink,
respectively.
[00102] For a multiple-access system (e.g., SC-FDMA, FDMA, OFDMA,
CDMA, TDMA, etc.), multiple terminals can transmit concurrently on the uplink.
For
such a system, the pilot subbands can be shared among different terminals. The
channel
estimation techniques can be used in cases where the pilot subbands for each
terminal
span the entire operating band (possibly except for the band edges). Such a
pilot
subband structure would be desirable to obtain frequency diversity for each
terminal.
The techniques described herein can be implemented by various means. For
example,
these techniques can be implemented in hardware, software, or a combination
thereof.
For a hardware implementation, which can be digital, analog, or both digital
and analog,
the processing units used for channel estimation can be implemented within one
or more
application specific integrated circuits (ASICs), digital signal processors
(DSPs), digital
signal processing devices (DSPDs), programmable logic devices (PLDs), field
programmable gate arrays (FPGAs), processors, controllers, micro-controllers,
microprocessors, other electronic units designed to perform the functions
described
herein, or a combination thereof. With software, implementation can be through
modules (e.g., procedures, functions, and so on) that perform the functions
described
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herein. The software codes can be stored in memory unit and executed by the
processors 1190 and 1150.
[00103] Figs. 12 and 13 depict block diagrams of example systems 1200, 1300
that provide and/or facilitate RUM accumulation based on sector performance
metrics
of a mobile AN. System 1200 comprises a module 1202 for obtaining a
performance
metric of a sector of a mobile RAN site. The module 1202 can further obtain a
performance metric of at least one neighboring sector. In at least one aspect,
the
performance metrics can be aggregated into a single aggregated metric of
wireless
communications of the mobile RAN site. System 1200 can further comprise a
module
1204 that establishes a rate at which devices within the sector accumulate
RUMs.
Module 1204 can establish the rate at least in part on a comparison of the
performance
rate for the sector and the performance rate(s) of the neighboring sector(s).
In one
particular aspect, module 1204 can establish the rate based on the performance
rate for
the sector and an aggregate performance rate of sectors of the mobile RAN
site.
[00104] System 1300 can comprise a module 1302 for obtaining wireless OTA
messages. The module can obtain first OTA message that comprises a performance
metric of a sector of a mobile AN. The module 1302 can further obtain a second
OTA
message that comprises a RUM. The first OTA message and/or second OTA message,
and information related thereto, can be maintained in a module 1306 for
storing data. In
addition to the foregoing, system 1300 can comprise a module 1304 for
forwarding
OTA messages to a serving base station. The module 1304 can forward, for
instance,
the first OTA message, or at least the performance metric, to the serving base
station. In
one particular aspect, a response to the first OTA message from the serving
base station
can determine whether the RUM is to be obeyed by system 1300. Such
determination
can be implemented by a module 1308 for executing process instructions, where
such
instructions are based at least in part on the performance metric of the
sector, a weight
of the RUM, or a combination of both.
[00105] What has been described above includes examples of aspects of the
claimed subject matter. It is, of course, not possible to describe every
conceivable
combination of components or methodologies for purposes of describing the
claimed
subject matter, but one of ordinary skill in the art may recognize that many
further
combinations and permutations of the disclosed subject matter are possible.
Accordingly, the disclosed subject matter is intended to embrace all such
alterations,
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modifications and variations that fall within the spirit and scope of the
appended claims.
Furthermore, to the extent that the terms "includes," "has" or "having" are
used in either
the detailed description or the claims, such terms are intended to be
inclusive in a
manner similar to the term "comprising" as "comprising" is interpreted when
employed
as a transitional word in a claim.
